I am running SP2 TB with a SP1 ECU. You will need a power commander for this to work.
There are mixed feelings about doing this, some say it is not worth it, and you get more mid HP with the SP1 TB. I think if this was the case, there would be a demand for them.
I like my SP1 with the SP2 TB, I think it is smoother, and it fuels better, but I do have a custom map. There is no troubles in setting it up, just get the SP2 boots as well, as they are a different size. The rest is just plug and play
This is great! i needed this info right now as well! i have code 8 "tps" and checked with multimeter and it's not a wire problem: just couldnt do very last check with test harness cuz i dont have one but i think i need to replace whole throttle body assembly on my 2001 so i figured if i have to buy it anyway maybe i should buy SP2 TB since i hear injectors are better so better throttle response and can anyone tell me if the TB size is larger (i think so).
stu494: can you confirm exactly what i would need? just TB and boots and power commander? do i need the TB wire harness from SP2? does SP1 airbox and velocity stacks fit on SP2 TB? and which pcIII would i buy SP1 or SP2 and what MAP?
Csteingraber, if you want to change over to the SP2 throttle bodies, you will need the Throttle bodies themselves, the rubber boots that go between the throttle bodies and the motor, the clamps for the boots, and the velocity stacks.
All cables are interchangeable, and the unit will just plug into your existing wiring harness, providing that what you pick up is complete. I don’t know about the airbox though, as I installed one of Turn One’s at the time. Thinking back, the bottom of the airbox box sat on top of the throttle bodies, so there will more than likely be a difference; SP1 TB’s are 54mm and the SP2 TB’s are 62mm. there are differences with the injectors as well… SP1’s had 4 holes per injector, and the SP2’s had 12; I don’t think you can change them around without too much mucking around.
Once installed, you will need to run a power commander, and have the bike mapped. That’s all there is to do.
Now for the good bits; if you are going to do this, consider running a bigger airbox, and possibly a snorkel. I ended up doing the whole lot in one hit… SP2 TB”s, Turn One CF airbox and snorkel. When I had mine Mapped, I was pushing 133 RWHP, but I know that is dependent on the dyno. The seat Dyno liked what happened; the bike was a lot smoother, fuel use was around the same, but the bike sounded like it was breathing better, and wanted to go harder.
As Mark says, there is proof that the SP1 TB’s will make more mid-range horsepower than the SP2’s, but the trade-off is that it will take away a lot of the jerkiness associated with the SP1. The call is yours; I am sure you could pick up both types of throttle bodies if you look hard enough and didn’t want to go through setting up the SP2 TB’s
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